M1 Headset mic input level too low on OP-Z

Hi Friends,
Just purchased an opz. I also have an M1 headset. When activating the external headset mic in input mode, I can BARELY hear my voice though the headset. I have the gain turned up all the way, and my mixer tracks are set to reasonable volumes. I tried adjusting the master volumes as well as the yellow knob output volume with no luck. When using the build in mic, the level is much better. What am I doing wrong? Is this a known issues with the M1 headset? I’d like to be able to hear my vocals while the opz is playing but so far, no luck. Any thoughts or suggestions appreciated.
With Gratitude,

Is it plugged in all the way? It’s tight to get it plugged in all the way.

Just checked. Yes, all connections are plugged in all the way, at least as hard as I can push. Could it be a problem with my unit (opz or headphone)? Not sure what else I can try.

Sorry, I’m not really sure… have you tried talking to teenage engineering? They would be the ones to talk to.